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<h2><a href="../../api/MagickCore/fx_8c.html" id="pfx-&gt;exception,_GetMagickModule">pfx-&gt;exception, GetMagickModule</a></h2>

<p>pfx-&gt;exception, GetMagickModule(), OptionError, "ImgNum", "lu bad for ImgListLen lu", (unsigned long) i, (unsigned long) pfx-&gt;ImgListLen); i = -1; } return i; }</p>

<p>#define WHICH_ATTR_CHAN \ (pel-&gt;ChannelQual == NO_CHAN_QUAL) ? CompositePixelChannel : \ (pel-&gt;ChannelQual == THIS_CHANNEL) ? channel : pel-&gt;ChannelQual</p>

<p>#define WHICH_NON_ATTR_CHAN \ (pel-&gt;ChannelQual == NO_CHAN_QUAL || \ pel-&gt;ChannelQual == THIS_CHANNEL || \ pel-&gt;ChannelQual == CompositePixelChannel \ ) ? (channel == CompositePixelChannel ? RedPixelChannel: channel) \ : pel-&gt;ChannelQual</p>

<p>static fxFltType GetHslFlt (FxInfo * pfx, ssize_t ImgNum, const fxFltType fx, const fxFltType fy, PixelChannel channel) { Image * img = pfx-&gt;Images[ImgNum];</p>

<p>double red, green, blue; double hue=0, saturation=0, lightness=0;</p>

<p>MagickBooleanType okay = MagickTrue; if(!InterpolatePixelChannel (img, pfx-&gt;Imgs[ImgNum].View, RedPixelChannel, img-&gt;interpolate, (double) fx, (double) fy, &amp;red, pfx-&gt;exception)) okay = MagickFalse; if(!InterpolatePixelChannel (img, pfx-&gt;Imgs[ImgNum].View, GreenPixelChannel, img-&gt;interpolate, (double) fx, (double) fy, &amp;green, pfx-&gt;exception)) okay = MagickFalse; if(!InterpolatePixelChannel (img, pfx-&gt;Imgs[ImgNum].View, BluePixelChannel, img-&gt;interpolate, (double) fx, (double) fy, &amp;blue, pfx-&gt;exception)) okay = MagickFalse;</p>

<p>if (!okay) (void) ThrowMagickException ( pfx-&gt;exception, GetMagickModule(), OptionError, "GetHslFlt failure", "lu g,g i", (unsigned long) ImgNum, (double) fx, (double) fy, channel);</p>

<p>ConvertRGBToHSL ( red, green, blue, &amp;hue, &amp;saturation, &amp;lightness);</p>

<p>if (channel == HUE_CHANNEL)   return hue; if (channel == SAT_CHANNEL)   return saturation; if (channel == LIGHT_CHANNEL) return lightness;</p>

<p>return 0.0; }</p>

<p>static fxFltType GetHslInt (FxInfo * pfx, ssize_t ImgNum, const ssize_t imgx, const ssize_t imgy, PixelChannel channel) { Image * img = pfx-&gt;Images[ImgNum];</p>

<p>double hue=0, saturation=0, lightness=0;</p>

<p>const Quantum * p = GetCacheViewVirtualPixels (pfx-&gt;Imgs[ImgNum].View, imgx, imgy, 1, 1, pfx-&gt;exception); if (p == (const Quantum *) NULL) { (void) ThrowMagickException (pfx-&gt;exception,GetMagickModule(), OptionError,"GetHslInt failure","lu li,li i",(unsigned long) ImgNum, (long) imgx,(long) imgy,channel); return(0.0); }</p>

<p>ConvertRGBToHSL ( GetPixelRed (img, p), GetPixelGreen (img, p), GetPixelBlue (img, p), &amp;hue, &amp;saturation, &amp;lightness);</p>

<p>if (channel == HUE_CHANNEL)   return hue; if (channel == SAT_CHANNEL)   return saturation; if (channel == LIGHT_CHANNEL) return lightness;</p>

<p>return 0.0; }</p>

<p>static inline fxFltType GetIntensity (FxInfo * pfx, ssize_t ImgNum, const fxFltType fx, const fxFltType fy) { Quantum quantum_pixel[MaxPixelChannels];</p>

<p>PixelInfo pixelinf;</p>

<p>Image * img = pfx-&gt;Images[ImgNum];</p>

<p>(void) GetPixelInfo (img, &amp;pixelinf);</p>

<p>if (!InterpolatePixelInfo (img, pfx-&gt;Imgs[pfx-&gt;ImgNum].View, img-&gt;interpolate, (double) fx, (double) fy, &amp;pixelinf, pfx-&gt;exception)) { (void) ThrowMagickException ( pfx-&gt;exception, GetMagickModule(), OptionError, "GetIntensity failure", "lu g,g", (unsigned long) ImgNum, (double) fx, (double) fy); }</p>

<p>SetPixelViaPixelInfo (img, &amp;pixelinf, quantum_pixel); return QuantumScale * GetPixelIntensity (img, quantum_pixel); }</p>

<p>static MagickBooleanType ExecuteRPN (FxInfo * pfx, fxRtT * pfxrt, fxFltType *result, const PixelChannel channel, const ssize_t imgx, const ssize_t imgy) { const Quantum * p = pfxrt-&gt;thisPixel; fxFltType regA=0, regB=0, regC=0, regD=0, regE=0; Image * img = pfx-&gt;image; ChannelStatistics * cs = NULL; MagickBooleanType NeedRelinq = MagickFalse; double hue=0, saturation=0, lightness=0; int i;</p>

<p>/* For -fx, this sets p to ImgNum 0. for [fx:...], this sets p to the current image. Similarly img. </p>
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